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We report a diaryldiselenide catalyst for cross-dehydrogenative nucleophilic functionalization of hydrophosphoryl compounds. The proposed organocatalytic cycle closely resembles the mechanism of the Atherton–Todd reaction, with the catalyst serving as a recyclable analogue of the halogenating agent employed in the named reaction. Phosphorus and selenium NMR studies reveal the existence of a P–Se bond intermediate, and structural analyses indicate a stereospecific reaction. 

Amide bonds are ubiquitous in peptides, proteins, pharmaceuticals, and polymers. The formation of amide bonds is a straightforward process: amide bonds can be synthesized with relative ease because of the availability of efficient coupling agents. However, there is a substantive need for methods that do not require excess reagents. A catalyst that condenses amino acids could have an important impact by reducing the significant waste generated during peptide synthesis. We describe the rational design of a biomimetic catalyst that can efficiently couple amino acids featuring standard protecting groups. The catalyst design combines lessons learned from enzymes, peptide biosynthesis, and organocatalysts. Under optimized conditions, 5 mol % catalyst efficiently couples Fmoc amino acids without notable racemization. Importantly, we demonstrate that the catalyst is functional for the synthesis of oligopeptides on solid phase. This result is significant because it illustrates the potential of the catalyst to function on a substrate with a multitude of amide bonds, which may be expected to inhibit a hydrogen-bonding catalyst.